Corrected: Radiation at 500 microsieverts/hr at Japan

(Agency corrects radiation level to 500 microsieverts per hour, not millisieverts. Corrects to show level was recorded on March 18, not Wednesday; and removes reference to highest level of radiation since crisis began.)

TOKYO (Reuters) - Radiation at the crippled Fukushima No.2 nuclear reactor was recorded at 500 microsieverts per hour on March 18, Japan's nuclear safety agency said on Wednesday.

Engineers have been trying to fix the plant's cooling system after restoring lighting on Tuesday.